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Role of a parallel magnetic field in two dimensional disordered clusters containing a few correlated electrons

Franck Selva·Jean-Louis Pichard
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Abstract

An ensemble of 2d disordered clusters with a few electrons is studied as a function of the Coulomb energy to kinetic energy ratio r_s. Between the Fermi system (small r_s) and the Wigner molecule (large r_s), an interaction induced delocalization of the ground state takes place which is suppressed when the spins are aligned by a parallel magnetic field. Our results confirm the existence of an intermediate regime where the Wigner antiferromagnetism defavors the Stoner ferromagnetism and where the enhancement of the Lande g factor observed in dilute electron systems is reproduced.

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Franck Selva, Jean-Louis Pichard. 2000-12-01. Role of a parallel magnetic field in two dimensional disordered clusters containing a few correlated electrons. https://doi.org/10.1209/epl%2Fi2001-00446-x

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